Malicious PDF — malware analysis report

Static analysis result for SHA-256 8e3138c5d61bfdf0…

MALICIOUS

PDF

78.5 KB Created: 2021-09-10 22:38:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 5be9206a077d52a1739a52745621255d SHA-1: 9492446df68ffc1fbf35c2adae1447ae8dda202d SHA-256: 8e3138c5d61bfdf052d7c1d314bc485a8e9a40b6022674c34745c65b137f7d28
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains embedded JavaScript and numerous external URIs, many of which are hosted on compromised or disposable domains, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. The presence of embedded JavaScript points to its use in executing malicious actions within the PDF.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL http://hastensandbreakfast.nl/userfiles/file/lijanelofiwokusupivurubi.pdf In PDF document text
    • http://www.goataxiservice.com/wp-content/plugins/formcraft/file-upload/server/content/files/16132493476f34---25653417146.pdfIn PDF document text
    • http://irk-yoga.ru/upload/files/wixitumozuri.pdfIn PDF document text
    • https://damiel.eu/userfiles/file/garivularaxiruxig.pdfIn PDF document text
    • http://volvo-cars.jp/js/upload/files/20582534281.pdfIn PDF document text
    • http://xn----9sbkvfu2aex3d.xn--p1ai/ckfinder/userfiles/files/daxuru.pdfIn PDF document text
    • http://zussobrance.sk/grafika/dokumenty/4503352001.pdfIn PDF document text
    • http://www.c-l-r-p.com/admin/ckfinder/userfiles/files/zivuradunoxawunivanofan.pdfIn PDF document text
    • https://nabsangram.com/userfiles/file/jonipuxalefa.pdfIn PDF document text
    • http://xn--h1acbpobggs.xn--p1ai/data/files/xuzusuzikotanejefadixe.pdfIn PDF document text
    • http://zeminyerkaplama.com/upload/ckfinder/files/3221883700.pdfIn PDF document text
    • http://hidropro.hu/upload/warazaxa.pdfIn PDF document text
    • https://elpollopaulino.com/cenavarra_userfiles/files/karifosugewinorinixe.pdfIn PDF document text
    • https://finestblogger.de/wp-content/plugins/super-forms/uploads/php/files/hrtiq0l56a32ks04vc7ifmmecq/57658863624.pdfIn PDF document text
    • https://walterchiropracticclinic.com/home/walter/public_html/ckfinder/userfiles/files/26877891307.pdfIn PDF document text
    • https://purpleleafestatebuyers.com/wp-content/plugins/formcraft/file-upload/server/content/files/161358ec073124---8438711874.pdfIn PDF document text
    • http://dfwsedan.com/nbloom/fckuploads/file/kefoburuvufijumo.pdfIn PDF document text
    • http://mdfgiare.com/upload/files/jobuvopeporu.pdfIn PDF document text
    • http://moretonassets.net/userfiles/najura.pdfIn PDF document text
    • http://duszek-lasu.pl/userfiles/file/25155066133.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/GLLx1DTH0VQ/uplcv?utm_term=pubg+for+apk+downloadPDF link annotation
    • http://alessandrotria.altervista.org/areap/ckfinder/userfiles/files/50469005717.pdfIn PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d02f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD02F 10604 bytes
SHA-256: fa812d470841f0820386a67902f221461f829e51944c61894fc2b7d53357ca0b
font_01_sfnt_off0000e81b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE81B 17180 bytes
SHA-256: 9605b3c2b1cb774b575efb1a0ae016c782c4451d5c564b5f720f9c2b1141a24a
font_02_sfnt_off00011475.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11475 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1